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Unlike other storage units, such as chests, shulker boxes keep their items when broken, which can be retrieved when placed again. Shulker boxes will drop as an item if pushed by pistons, and can be placed using dispensers. When holding a shulker box with items inside, the items will be listed as properties.
Items inside the shulker box are listed below the block type properties.
Shulker boxes can be stored in other containers, though they cannot be stored in other shulker boxes.
A shulker box has 27 inventory slots, the same number as a chest.
By default, the GUI of a shulker box is labeled "Shulker Box", but this name can be customized by naming it in an anvil before placing it, or by changing the CustomName tag using the /blockdata command.